Fence Post Calculator
How many posts do I need for my fence? Enter your total fence length, post spacing and the number of gates — this calculator gives you the exact post count and concrete bags.
Estimate
| Posts needed (line + terminal + gate) | 28 |
|---|---|
| Terminal posts (end/corner/gate) | 4 |
| Concrete bags (volume-based) | 84 |
| Post + concrete cost | $1,162 |
How the post math works
The formula is deterministic: divide your fence run by the post spacing, round up, then add 1 for the final post. Every gate adds 2 posts (hinge + latch). Concrete is calculated from the hole volume (minus post displacement) divided by the bag yield — for a 4×4 post in a 10-inch hole, roughly 2–3 bags (50 lb) per post depending on depth. Planning estimate only — verify local frost depth and code.
Fence post spacing rules of thumb
- Wood privacy fence: 6–8 ft post spacing.
- Chain link: 8–10 ft spacing.
- Every gate needs 2 additional posts (hinge post + latch post).
- Corners and ends always need a post — the formula already includes them.
Post depth matters more than post count
A common DIY mistake is setting posts too shallow. Aim for at least one-third of the above-ground post height, with a 2 ft minimum, and always below your local frost line. Posts that heave in winter throw panels out of level and loosen gate hardware within a season or two.
Frequently asked questions
How far apart should fence posts be?
Wood and vinyl panel fences: 6–8 ft. Chain link line posts: 8–10 ft. Tighter spacing adds wind resistance but raises cost — for a 200 ft fence, moving from 8 ft to 6 ft spacing adds roughly 8 posts and 16 concrete bags.
How many bags of concrete per post?
Two 50 lb bags per 4×4 post at 6 ft height is the standard. Use the result above as the baseline, then add bags for any post going into soft or sandy soil.
Do gate posts need to be different from line posts?
Yes — they carry the swinging gate's weight, so use heavier material and concrete them in fully. The calculator already includes 2 posts per gate in the total.